1. Field of the Invention
The present invention relates to a perpendicular magnetic recording head which performs a recording action by applying a recording magnetic field perpendicularly to a recording medium plane.
2. Related Background Art
As is well-known, a perpendicular magnetic recording head includes a main magnetic pole layer and a return yoke layer which have front end faces exposed at a surface opposing a recording medium (medium-opposing surface) and are magnetically coupled to each other on the deeper side in the height direction of the medium-opposing surface, a magnetic gap layer interposed between the main magnetic pole layer and return yoke layer on the medium-opposing surface, and a coil layer inducing a recording magnetic field between the main magnetic pole layer and return yoke layer upon energization. The recording magnetic field induced between the main magnetic pole layer and return yoke layer perpendicularly enters a hard film of the recording medium from the front end face of the main magnetic pole layer and returns to the front end face of the yoke layer through a soft film of the recording medium. This performs magnetic recording at a part opposing the front end face of the main magnetic pole layer. The size in the track width direction of the front end face of the main magnetic pole layer, i.e., recording track width size, has been becoming narrower as hard disk drives have been attaining higher recording densities.
In a perpendicular magnetic recording head having a narrowed track, how to suppress side fringing at the time of skewing has become a problem. It has conventionally been well-known, as described in Japanese Patent Application Laid-Open No. 2005-92929, for example, to provide a pair of side shield layers on both sides in the track width direction of the magnetic pole part of the main magnetic pole layer, so that lateral magnetic fluxes leaking from both side faces in the track width direction of the magnetic pole part are absorbed by the pair of side shield layers without reaching the recording medium, thus suppressing side fringing. It has conventionally been typical for the pair of side shield layers to be formed rectangular by photolithography.